Combined stabilizing and gas conversion process



April 6, 1937. M. P. YOUKER COMBINED STABILIZING AND GAS CONVERSIONPROCESS Filed July 5, 1935 BY Waff 2% A TTORNEYS.

Patented Apr. 6, 1937 COMBINED STABILIZIN G AND GAS CONVER- SION PROCESSMalcolm r. Youker, amneville, x13., asslgnor to Phillips PetroleumCompany, Bartlesville, Okla., a corporation of Delaware Application July5, 1933, Serial No. 679,116

(Cl. ISG-10) 9 Claims.

This invention relates to the manufacture of stable motor fuel from veryvolatile hydrocarbon liquids and gases such as are contained in naturalgas and in the gases which result from the cracking of oils. An objectof the invention is to provide a process by which a mixture ofhydrocarbon materials, at least a substantial portion of which isysuillciently stable to be incorporated in motor fuel having a boilingpoint above 100 F. and a 10 portion of which is of lower boiling rangeand too volatile to be incorporated in motor fuel, may be treated tosimultaneously convert a portion of the more volatile material to lessvolatile material of high anti-knock value and a portion l5 of the lessvolatile material to material of similar volatility but of higheranti-knock value and to rectify and stabilize the resulting products.Other objects of the invention will be made apparent in the followingdiscussion. My new process may be understood from the description givenbelow which refers to the accompanying drawing on which a form ofapparatus, by which my process may be carried out, is illustrated inside elevation. p

In my co-pending application, Serial No. 610,513, Patent No. 2,040,455,granted May 12, 1936, I have disclosed 'a process whereby raw unstableliquefied gases may iirst be rectified ina fractionating column toobtain a fraction of suitable volatility for inclusion directly intomotor fuel while at the same time the more volatile `fractions separatedin the column may be passed through a conversion tube wherein a portionof the more volatile material is converted to material of lowervolatility suitable for inclusion In motor fuel and discharged into thesame column so that simultaneous rectification of the converted materialand the raw material is accomplished and the portions of both suitablefor motor fuel may be withdrawn together from the column. By such aprocess no conversion of the less volatile constituents of the rawcharge takes place. By my present process I propose to pass the entireraw liqueed gas through a conversion tube so that the portion which isof suitable volatility for motor fuel will alsoundergo conversionreactions which will improve its' anti-knock value w'hile at the sametime the more volatile portions are being converted to less volatilematerial suitable for conversion to motor fuels. The entire convertedmaterial is then rectified, the portion suitable for stable motor .fuelwithdrawn from the process. the fixed gases discharged from the processand the portions too volatile for motor fuel but capable of a furtherconversion are returned to the conversion tube.

Referring `to the drawing in one method oi' operation, unstabilizednatural gasoline having a substantial portion boiling over F. will bepumped by a pump 2 through a pipe I, in which is mounted a valve l intoand through a conversion tube 5, which leads through a furnace 6, andinto a fractionating column I2. A burner l supplies the means forheating the furnace 6. The material passing through the conversion tube5 will be heated to conversion conditions in the furnace B. A backpressure valve I0 is mounted in the outlet of the tube 5 to permitmaintaining the materials undergoing conversion under any desiredpressure. The heated converted materials, after passing through valveI0, will pass into an intermediate portion of a fractionating column I2which is equipped with bubble trays II. Upon entering the fractionatingcolumn I2, the converted materials are in a partially vaporized state,and will separate int'o a vapor and a liquid portion. The vapors willtravel upward through the column I2 over the bubble trays II and thosereaching the top of the column I2 will pass therefrom through a pipe 20which leads through a condenser 2l and delivers into an accumulator 22.A portion of the vapors which pass through the pipe 20 and condenser 2|will be condensed therein and as a result a mixture of gases and liquidswill iiow from the pipe 20 into the accumulator 22. Fixed gases whichwill accumulate in the accumulator 22 will be discharged through a pipe23 in which is mounted a back pressure valve 2l. Aportion of the liquidwhich will collect in the accumulator 22 will be delivered therefromthrough a pipe 25 in which is mounted 4a valve 26 into the upperlpart ofthe fractionating column I2 and will iiow thence downward over thebubble plates II therein and will contact thereon and condense a portionof the vapors which rise through the fractionating column I2 and thecondensate thus produced will flow downward through the column I2 overthe bubble plates II. A portion of this condensate which will iiowdownward will be withdrawn from the column I2 through a ,pipe 21 inwhich is mounted a valve 28 and which is connected into the column I2 ata point intermediate the points of entry of the pipe 5 through which theconversion materials enter the column I2 and the pipe 26, through whichreflux material is delivered to the column I2. 'I'he quantity of refluxliquid delivered through the pipe 2B into the upper part of thefractionating column I2 will be so regulated as to condense within thecolumn I2 that portion of the vapors which rise through thefractionating column I2 which have a vapor pressure suiciently low tosatisfy the requirements for the liquids obtained from the process.Increasing the quantity of liquid refluxed will increase the vaporpressure of the liquid obtained from the column I2 through the pipe 21and vice versa. 'I'he gravity and end point of the liquid obtainedthrough the pipe 21 will be regulated by regulating the quantity ofliquid so obtained and increasing the quantity of liquid so obtainedwill raise the end point of such liquid and vice versa. Liquid materialsheavier than those withdrawn through the pipe 21 will flow downward tothe bottom of the column I2 where a portion of them will be withdrawnthrough a pipe I3 by a pump I4 and pumped through a rebolling tube IBwhich leads through the furnace 6 and thence into the bottom of thefractionating column I2. Heat is imparted to this material which ispassed through tube I6 into the column I2 to vaid in ihe rectificationstep carried out therein. The excess of this material which willaccumulate in he bottom of the column I2 will be withdrawn through apipe I8 in which is mounted a valve I9. his material and the liquidwithdrawn through the pipe 21 will be passed therefrom through foolersto storage tanks, neither of which are shown.

Liquids collected in the accumulator 22 will be delivered by a pump 3|)through a pipe 29 having mounted therein a valve 3| into and through theentire conversion tube 5. A pipe having mounted therein a valve 9 isconnected into the pipe 29 and leads to an intermediate point in theconversion tube 5. In another method oi operation by opening valve 9 andclosing valve 3| the pump 30 will pump liquid from the accumulator 22through pipe 29, into pipe B, through valve 9 and thence through a laterportion of the conversion tube 5. In this way this material which isstill too volatile to be included in the motor fuel withdrawn from thecolumn I2 through pipe ".1 will be reprocessed in the conversion tube 5and the maximum quantity of material suitable for use as motor fuel willbe thus obtained.

It will be found desirable in some cases to add to the charge a quantityof comparatively less volatile motor fuel as it will be found that suchmaterial will combine quite readily with the lighter constituents of theliquefied gases, and result in smaller fixed gas production.

In passing through the conversion tube 5 the portion of the unstabilizedcharging stock which is too volatile to be included in motor fuel willundergo polymerization reactions and at least a part of this volatilematerial will be polymerized to less volatile liquids which may besatisfactorily included in motor fuel. At the same time the remainingportion of the unstabilized charging stock which is already of suitablevolatility for inclusion in motor fuel will be reformed and itsanti-knock rating improved without substantially changing its volatilitycharacteristics.

In practicing my process the pressures maintained in the conversion tube5 may be any pressures from atmospheric up to pressures of 10,000 poundsper square inch or above. The maximum pressure limits being subjectlargely to the commercial availability of structural materials capabieof withstanding such pressures. However, I ind it more desirable to usepressures of at least 500 pounds per square inch and depending on thetype materials to be processed and the results desired, I find pressuresof around 3000 pounds per square inch particularly preferable.

Similarly, temperatures attained in the conversion tube will usually lieabove 750 F. and often as high as 11507 F. or higher, this conditionalso being subject to variation in stocks treated and results desired,as well as the pressures employed. Temperatures of 900 F. to 1100'D F.are most usually employed.

A pressure of 100 to 500 pounds per square inch will preferably bemaintained in the fractionating column I2 and accumulator 22 and theinterconnecting pipe lines. However, either higher or lower pressuresmay be maintained in these parts of the equipment.

Through the use of this process unstabilized gasoline obtained fromconventional natural gasoline plants or from a conventional gasolineplant used to separate gasoline from the cracked gases emanating fromcracking stills may be stabilized and not only may a larger yield ofmaterial of suitable volatility for motor fuels be obtained than hashitherto been possible but the nal product will have a comparativelyhigher antiknock rating.

While I have described in detail one method of carrying out my newprocess, I do not wish to be limited to these particular details butintend to claim all the advantages which are inherent in my new process.

I claim:

l. A process for converting and stabilizing gasoline containingsubstantial quantities of hydrocarbons too unstable to be incorporatedin motor fuels, which comprises subjecting the said gasoline toconversion conditions such that at least a portion of said hydrocarbonswhich are too unstable to be incorporated in motor fuels are convertedto materials which are suiciently stable to be incorporated in motorfuels while simultaneously reforming that portion of the said gasolinewhich was suiiiciently stable originally to be incorporated in motorfuels, rectifying the total converted material to obtain xed gases,motor fuel and a fraction intermediate in volatility between the fixedgases and motor fuel, and returning the said intermediate fraction forreprocessing.

2. A process for converting and stabilizing gasoline containingsubstantial quantities of hydrocarbons too unstable to be incorporatedin motor fuels which comprises subjecting the said gasoline toconversion temperatures of between 750 F. and 1150 F. whereby at least aportion of the said hydrocarbons which are too unstable to beincorporated in motor fuels are converted to materials which aresuiilclently stable to be incorporated in motor fuels whilesimultaneously reforming that portion of the said gasoline which wassufiiciently stable originally to be incorporated in motor fuels,rectifying the total converted material to obtain fixed gases. motorfuel and a fraction intermediate in volatility between the xed gases andmotor fuel, and returning the said intermediate fraction forreprocessing.

3. A process for converting and stabilizing gasoline containingsubstantial quantities of hydrocarbons which are too unstable to beincorporated in motor fuels, which comprises subjecting the saidgasoline to conversion temperatures and to la pressure between 500pounds per square inch and 3000 pounds per square inch, whereby atleasta portion of the said hydrocarbons which are too unstable to beincorporated in motor fuels are converted to materials which aresufficiently stable to be incorporated in motor fuels, whilesimultaneously reforming that portion of the original material which wassuiiiciently stable originally to be incorporated in motor fuels,rectifying the total converted material to obtain xed gases, motor fueland a fraction intermediate in volatility between the xed gases andmotor fuel and returning the said intermediate fraction forreprocessing.

4. A process for converting and stabilizing gasoline containingsubstantial quantities of hydrocarbons which are too unstable to beincorporated in motor fuels which comprises subjecting the saidgasolines to a temperature between 750 F. and 1150 F. and a pressurebetween 500 pounds per square inch and 3000 pounds per square inchwhereby at least a portion of the said hydrocarbons which are toounstable to be incorporated in motor fuels are converted to materialswhich are sufiiciently stable to be incorporated in motor fuels whilesimultaneously reforming that portion of the said gasoline which wassufficiently stable originally to be incorporated in motor fuels,rectifying the total converted material to obtain xed gases, motor fueland a fraction intermediate in volatility between the xed gases andmotor fuel, and returning the Said intermediate fraction forreprocessing.

5. A process for converting and stabilizing unstable gasoline containingsubstantial quantities of hydrocarbons which are too unstable to beincorporated in motor fuels, which comprises passing the unstablegasoline in a restricted stream through a heating zone and thereinsubjecting the same to temperatures between '750 F. and 1 150 F. whilemaintaining the same under a pressure between 500 and 3000 pounds persquare inch for a time sumcient to convert a portion of saidhydrocarbons which are too unstable to be incorporated in motor fuels tomaterials which are suiiiciently stable to be incorporated in motorfuels while simultaneously reforming that portion of the originalmaterial which was suficiently stable originally to be incorporated inmotor fuels, then introducing said stream into a rectification zone,subjecting the material in the rectification zone to a reflux condensateformed from a portion of said material and thereby fractionating stablemotor fuel from material lighter and heavier than said motor fuel, andpassing a portion of the last mentioned lighter material with theunstable gasoline through the heating zone.

6. A process according to claim l, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

7. A process according to claim 2, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

8. A process according to claim 3, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

9. A process according to claim 4, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

MALCOLM P. YOUKER.

DISOLAIM ER 2,076,0l3.-Malc0lm P. Youker, Bartlesville, Okla.

Patent dated April 6, l937.

CONVERSION PROCESS.

COMBINED STABILIZING AND GAS Disclalmer filed April 2l, 1938, by theassignee, Phillips Petroleum Company.

Herebyenters disclaimer to the subject matter of claims l to 4 inclusiveexcept insofar as said claims apply to a process in which unstablenatural gasoline constitutes the stock to be treated by the process.

[Ocial Gazette May 24, 1938.]

ble to be incorporated in motor fuels, while simultaneously reformingthat portion of the original material which was suiiiciently stableoriginally to be incorporated in motor fuels, rectifying the totalconverted material to obtain xed gases, motor fuel and a fractionintermediate in volatility between the xed gases and motor fuel andreturning the said intermediate fraction for reprocessing.

4. A process for converting and stabilizing gasoline containingsubstantial quantities of hydrocarbons which are too unstable to beincorporated in motor fuels which comprises subjecting the saidgasolines to a temperature between 750 F. and 1150 F. and a pressurebetween 500 pounds per square inch and 3000 pounds per square inchwhereby at least a portion of the said hydrocarbons which are toounstable to be incorporated in motor fuels are converted to materialswhich are sufiiciently stable to be incorporated in motor fuels whilesimultaneously reforming that portion of the said gasoline which wassufficiently stable originally to be incorporated in motor fuels,rectifying the total converted material to obtain xed gases, motor fueland a fraction intermediate in volatility between the xed gases andmotor fuel, and returning the Said intermediate fraction forreprocessing.

5. A process for converting and stabilizing unstable gasoline containingsubstantial quantities of hydrocarbons which are too unstable to beincorporated in motor fuels, which comprises passing the unstablegasoline in a restricted stream through a heating zone and thereinsubjecting the same to temperatures between '750 F. and 1 150 F. whilemaintaining the same under a pressure between 500 and 3000 pounds persquare inch for a time sumcient to convert a portion of saidhydrocarbons which are too unstable to be incorporated in motor fuels tomaterials which are suiiiciently stable to be incorporated in motorfuels while simultaneously reforming that portion of the originalmaterial which was suficiently stable originally to be incorporated inmotor fuels, then introducing said stream into a rectification zone,subjecting the material in the rectification zone to a reflux condensateformed from a portion of said material and thereby fractionating stablemotor fuel from material lighter and heavier than said motor fuel, andpassing a portion of the last mentioned lighter material with theunstable gasoline through the heating zone.

6. A process according to claim l, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

7. A process according to claim 2, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

8. A process according to claim 3, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

9. A process according to claim 4, wherein the rectification takes placeunder a pressure between 100 pounds per square inch and 500 pounds persquare inch.

MALCOLM P. YOUKER.

DISOLAIM ER 2,076,0l3.-Malc0lm P. Youker, Bartlesville, Okla.

Patent dated April 6, l937.

CONVERSION PROCESS.

COMBINED STABILIZING AND GAS Disclalmer filed April 2l, 1938, by theassignee, Phillips Petroleum Company.

Herebyenters disclaimer to the subject matter of claims l to 4 inclusiveexcept insofar as said claims apply to a process in which unstablenatural gasoline constitutes the stock to be treated by the process.

[Ocial Gazette May 24, 1938.]

